In recent years, research and development into how to dispose an object having various specific functions on an inner surface of a pneumatic tire has been performed.
For example, attachment methods are known in which a tire tag (radio frequency identification tag), a chip, or a sound-absorbing member is attached to an innerliner of a green tire using a surface fastener such as a hook and loop fastener or a hook and hook fastener (Japanese Unexamined Patent Application Publication Nos. 2005-517581A and 2006-044503A).
The surface fasteners proposed in Japanese Unexamined Patent Application Publication Nos. 2005-517581A and 2006-044503A have preferred embodiments which exhibit relatively strong engagement force when attached, and engagement on a surface can be achieved regardless of some misalignment during the attaching operation. However, when subjected to high speed rolling motion in a state of relatively elevated temperatures, deformation and compaction is repeated over an extended period of time. As a result, partial physical deterioration in the surface fastener is produced. As this deterioration progresses, deterioration and decline over time of the engagement force of an entirety of the surface fastener occurs. This leads to difficulties in retaining a desired engagement force over an extended period of time.
In light of this, the present inventors have proposed a pneumatic tire which includes a separatable pair of mechanical fasteners, wherein a first fastener of the pair of separatable pair of mechanical fasteners is provided on a tire inner surface (Japanese Unexamined Patent Application Publication Nos. 2012-025318A and 2012-240465A). These pneumatic tires are free of the problems described above and in particular, the obtained engagement force is great and is essentially free of variations (positional variation within the tire and variation from tire to tire). Furthermore, the engagement force deteriorates/declines minimally over time due to extreme usage conditions including deformation and compaction caused by high speed tire rolling motion in a state of relatively elevated temperatures being repeated for an extended period of time; and the desired engagement force can be maintained over an extended period of time.
As an approach to an attachment method for one fastener to the tire inner surface which, the present inventors have proposed individually embedding the fasteners in a tread rubber and vulcanizing the tire, and a mechanical fastener composed of at least two fastener members that is a first mechanical fastener of a separatable pair of mechanical fasteners which is disposed on a tire inner surface, and the two fastener members form the first fastener of the pair of mechanical fastener on a tire inner surface by fixing together while sandwiching a rubber layer, which is a tire component, or a rubber-coated fiber reinforced member (Japanese Unexamined Patent Application Publication No. 2012-025318A). This approach is superior from the perspective of strength of obtained engagement force, variation in the strength of this force, and reliability of engaging operations.
The present inventors have also proposed that at least two fastener members are fixed together while sandwiching a woven fabric or nonwoven fabric made of fibers (Japanese Unexamined Patent Application Publication No. 2012-240465A).
However, with these approaches, depending on the form of the fastener and the position where it is attached, the desired attachment strength may not be obtained, and the durability may decrease.
It is desirable for the attachment strength of the mechanical fastener to be greater and have a longer lifetime so that it can have application to objects having a specific function disposed inside the tire that have certain characteristics (mass, size, form, and the like).